The invention relates to a system for cleaning a surface. The system includes means for storing a cleaning liquid, means for dispensing the liquid to the surface to be cleaned and means for suctioning the liquid along with any dirt, and the like, that has been washed from the surface or dissolved in the liquid from the surface.
The prior art includes wet/dry suctioning systems which are adapted to pick up dispensed liquid and wet materials from a surface. Such suctioning systems typically include a collection tank, a take-up hose for transmitting the liquid or the wet materials from the surface to the collection tank and a suction motor, typically communicating with the tank, for generating a vacuum in the hose.
A surface can be cleaned more easily by spreading a cleaning liquid, such as a solution of water and detergent, across the surface. The surface can be a floor, a carpet or other surface. The liquid facilitates cleaning by dissolving and lifting off dirt, and the like, from the surface to be cleaned. Furthermore, the subsequent suctioning helps to dry the surface or carpet by lifting away the liquid and wet material from the surface.
Accordingly, liquid dispensing and suctioning systems have been developed to dispense cleaning liquid to a surface or carpet to be cleaned and to thereafter suction the liquid from the surface after the liquid has dissolved or lifted off dirt, and the like. Some of these liquid dispensing and suctioning systems are entirely self contained. Others are developed as attachments to an intake hose or wand of a standard wet/dry suctioning system. The liquid may be supplied to the attachment from an external source through a hose or tube or the liquid may be carried on the cleaning attachment within a tank.
In some systems, liquid may drip continuously through a nozzle leading from a liquid supply container. However, it is advantageous to selectively control the dispensing of liquid from the liquid dispensing and suctioning systems. Such control may be achieved, for example, by a manually operable trigger for opening a dispensing nozzle or valve. Liquid may be dispensed periodically or continuously.
In a system that is the subject of pending U.S. Application Pat. No. 07/282,103, filed Dec. 9, 1988, there is a common unit that is applied at the carpet or the surface being cleaned and which both delivers the liquid to the carpet or surface and suctions up that liquid. If the liquid dispensing outlet and suction nozzle of that unit are located near each other, liquid dispensed through the outlet is suctioned into the suction nozzle before it is delivered to the carpet or surface. The liquid migrates along the underside of the housing of the nozzle system into the suction inlet without wetting the carpet or other surface and thus without cleaning it. Enlarging the distance between the liquid outlet and the suction nozzle enlarges the surface area of the underside of the nozzle that contacts the carpet or surface. Bringing the entire dispensing outlet to the carpet or surface being cleaned has the same effect. It is desirable to limit or reduce the surface area of the nozzle contacting the carpet.